Internal combustion engines are still the predominant means for propelling motorized vehicles. They are proven to offer many advantages over alternative mechanisms, among these being cost and convenience. These engines have been used in gasoline and diesel engines, for example, such engines as used in automobiles, trucks, hydraulics, turbines, heavy equipment, and the like. Such engines can require fluid filtration for a variety of working fluids.
As one example, high pressure common rail (HPCR) fuel systems may require a filtration device for filtering particles as low as 5 micron and lower. Thus, there is a need to provide reliable fine filtration of fuel to reduce engine wear. Further, there is a need to further improve fine filtration and additive release configurations, and particularly in engines employing HPCR fuel systems.
As one other example, such engines can require lubrication filtration, where a circulating lubricant, such as oil, is usually employed as the working fluid. Filters have been commonly used to filter oil to remove contaminants, thereby protecting a combustion engine and preventing damage to the engine and its components lubricated by the oil. One example of a contaminant or by-product of combustion is the generation of acids in the ring zone of the engine. Acids can degrade the quality of the oil and shorten oil drain intervals, and if the oil is not changed, can reduce the intended effectiveness of the oil thereby leading to engine damage or failure. The concept of introducing additives to remove and neutralize engine generated acids is known, and intended to extend oil drain intervals without changing oil additive package chemistry. It is believed that this concept works in the following manner. Where acids generate in the ring zone of the engine, a weak-base forms an acid-base pair with the engine generated acid. In many cases, the weak base may already be present in the oil. The weak base begins neutralization of the engine generated acid, and carries it away from the ring zone to the filter. In the filter, an immobilized strong-base will “grab” the acid away from the weak base to form an acid-base pair that is trapped by the immobilized strong base, thereby neutralizing the acid. The weak base is then free to react with more acids in the ring zone, carrying them back to the immobilized base. However, efficient filtration is critical to extend oil drainage intervals, and there is still a need to further improve upon lubrication filtration and improve upon introducing additives for neutralizing acids.
More generally, there is a need to provide reliable fine filtration for a variety of working fluids so as to reduce engine wear. There also is a need to further improve upon introducing additives for any filtering purpose, so as to provide efficient filtration and extend the useful life of working fluids. In addition to improving, for example, fine filtration in HPCR fuel systems and improving acid neutralization in lube filtration, an improved filtration device as described herein below can provide additional benefits for introducing an additive, and may be used in other fluid filtration applications, for example, to increase lubricity, to protect against corrosion, to aid in combustion, or to otherwise treat or enhance a working fluid.